Does an emergent democracy have an obligation to prosecute its former dictators for crimes against humanity-for what Arendt and Kant called "radical evil"? What impact will such prosecutions have on the future of democracy? In this book, Carlos Santiago Nino offers a provocative first-hand analysis of developments in Argentina during the 1980s, when a brutal military dictatorship gave way to a democratic government. Nino played a key role in guiding the transition to democracy and in shaping the human rights policies of President Raúl Alfonsín after the fall of the military junta in 1983. The centerpiece of Alfonsín's human rights program was the trial held in a federal court in Buenos Aires in 1985, which resulted in the convictions of five of the leading members of the junta that ruled the country from 1976 to 1983. Placing the Argentine experience in the context of the war crimes trials at Nuremberg, Tokyo, and elsewhere, Nino examines the broader questions raised by human rights trials. He considers their political repercussions and their potential for strengthening the new democratic government. He explains why prosecutions for human rights violations should be grounded on a theory of the criminal law that emphasizes the preventive rather than retributive functions of punishment. Nino rejects the obligation to punish perpetrators of radical evil and argues instead for a more forward-looking duty-to safeguard democracy. This, he believes, is what ultimately justified the Argentine trials and should be the focus of any international action.